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122問 • 6ヶ月前
  • Liane
  • 通報

    問題一覧

  • 1

    What is a solution?

    A homogeneous mixture composed of two or more substances.

  • 2

    In a salt water solution, what is the solvent?

    Water

  • 3

    Which component is usually present in a larger amount in a solution?

    Solvent

  • 4

    What term describes the substance that is dissolved in a solution?

    Solute

  • 5

    What interactions must be overcome for solution formation?

    Solute-solute and solvent-solvent interactions

  • 6

    What happens to NaCl when it dissolves in water?

    The ions separate and interact with water molecules.

  • 7

    What is solubility?

    The maximum quantity of solute that can dissolve in a specific amount of solvent at a particular temperature.

  • 8

    How is a supersaturated solution defined?

    A solution containing more solute than can normally dissolve at a given temperature.

  • 9

    If a solution contains less solute than its solubility at a certain temperature, how is it classified?

    Unsaturated

  • 10

    Which describes the interaction between the separated ions of salt and the surrounding water molecules?

    Solute-solvent interaction

  • 11

    What term describes a solution that contains less than the maximum amount of dissolved solute and can still dissolve more solute?

    Unsaturated

  • 12

    Which type of solution contains more dissolved solute than is normally possible at a given temperature and pressure, often leading to crystal formation upon cooling or seeding?

    Supersaturated

  • 13

    When the concentration of a solute in solution equals its solubility at a certain temperature and pressure, how is the solution described?

    Saturated

  • 14

    According to general trends, how does increasing temperature generally affect the solubility of solids in liquids?

    Increasing temperature increases solubility.

  • 15

    Which principle states that an increase in pressure increases the solubility of gases in liquids?

    Henry's Law

  • 16

    What phrase is used to describe the tendency of polar solutes dissolving best in polar solvents and nonpolar in nonpolar?

    Like dissolves like

  • 17

    Which of the following combinations would likely be highly soluble: nonpolar solute with nonpolar solvent, or polar solute with nonpolar solvent?

    Nonpolar solute with nonpolar solvent

  • 18

    What are some common examples of solid-in-liquid solutions?

    Salt in water, Sugar in water

  • 19

    Which factor does NOT directly affect the solubility of a solid in a liquid?

    Partial pressure

  • 20

    Alloys such as brass and bronze are examples of which type of solute-solvent combination?

    Solid in solid

  • 21

    The solubility of gases in liquids increases with which condition?

    Increasing partial pressure

  • 22

    When water vapor is present in air (composed of N₂, O₂, CO₂), which type of solution is formed?

    Gas in gas solution

  • 23

    Which of the following is a key factor that enhances the rate at which a solid dissolves in a liquid?

    Agitation (stirring)

  • 24

    Which of the following ions form compounds that are ALWAYS soluble in water?

    Nitrate (NO3-), Group 1 ions (Li+, Na+, K+, Rb+, Cs+), Ammonium (NH4+), Acetates

  • 25

    Which of the following salts is most likely to form a precipitate in water?

    Lead(II) sulfate (PbSO4)

  • 26

    What is a common exception for the solubility of sulfate salts?

    Ba2+, Ca2+, Sr2+, Pb2+, Hg2+, Ag+

  • 27

    Chromates are insoluble except with which ions?

    Group 1 ions, NH4+

  • 28

    Which group of compounds are always soluble, regardless of the cation or anion they are paired with?

    Nitrates, Acetates

  • 29

    Halides (Cl-, Br-, I-) are generally soluble. Which ions are exceptions, making the corresponding halides insoluble?

    Pb2+, Ag+, Hg2+

  • 30

    Which statement is TRUE about the solubility of hydroxide (OH-) compounds?

    Hydroxides are insoluble except with Group 1, NH4+, Ba2+, Ca2+, and Sr2+

  • 31

    If a salt contains a Group 1 cation, what can be said about its solubility in water?

    It is always soluble.

  • 32

    Which of the following compounds is insoluble in water?

    Calcium phosphate (Ca3(PO4)2)

  • 33

    Why are solubility rules important in chemistry?

    They help predict whether a substance will dissolve in water., They are essential for writing net ionic equations., They aid in preparing chemical solutions.

  • 34

    Which of the following best describes molarity?

    Moles of solute per liter of solution

  • 35

    Select all correct units commonly used to express concentration in chemistry.

    Molarity (mol/L), Percent concentration (%), Molality (mol/kg), Normality (eq/L), Parts per million (ppm)

  • 36

    Why is it important to use the correct and consistent unit of concentration in chemical experiments?

    To ensure accurate calculations and meaningful comparisons

  • 37

    Which expression correctly represents mass percent (% w/w)?

    (grams of solute / grams of solution) × 100

  • 38

    What is the definition of molality (m)?

    Moles of solute per kilogram of solvent

  • 39

    What does the process of dilution involve in terms of solute and solvent?

    Adding more solvent to decrease concentration while keeping the amount of solute unchanged.

  • 40

    What is the correct formula for dilution relating the concentrations and volumes before and after the process?

    C1V1 = C2V2

  • 41

    Which step comes FIRST when preparing a dilute solution from a concentrated stock solution?

    Measure a volume V1 from a stock solution with known concentration C1.

  • 42

    During the dilution process, what happens to the amount of solute present in the solution?

    It remains unchanged.

  • 43

    Why is dilution commonly performed in the laboratory?

    To prepare solutions from a more concentrated stock solution.

  • 44

    When 60 mL of 85% by volume H3PO4 is diluted to a total volume of 1.0 L, what is the final concentration by volume of the solution?

    5.10%

  • 45

    Given a solution with 245.0 g of H2SO4 dissolved in 1.000 L of solution (molar mass = 98.086 g/mol), what is the normality (N) of H2SO4 if it has two ionizable protons?

    5.0 N

  • 46

    Which of the following best defines 'percent by volume' in a solution?

    (Volume of solute/Volume of solution) × 100%

  • 47

    How many milliliters of an 85% by volume H3PO4 are required to prepare exactly 1.0 L of a 5.10% by volume solution?

    60 mL

  • 48

    A concentrated ammonia solution contains 28.0% w/w NH3 and has a density of 0.899 g/mL. What additional information is needed to calculate the molarity of the solution?

    The molar mass of NH3

  • 49

    What taste is characteristic of acids?

    sour

  • 50

    Which color does blue litmus paper turn in the presence of an acid?

    red

  • 51

    What gas is produced when acids corrode metals?

    hydrogen gas

  • 52

    According to the Arrhenius definition, what does a base produce in aqueous solution?

    OH⁻ ions

  • 53

    What ion is formed when H⁺ associates with water in solution?

    hydronium ion (H₃O⁺)

  • 54

    What is a key limitation of the Arrhenius definition of bases?

    It only includes substances that contain OH⁻ ions as bases.

  • 55

    In the Bronsted-Lowry definition, what is an acid?

    A proton donor

  • 56

    After a Bronsted-Lowry acid donates a proton, what does it become?

    Conjugate base

  • 57

    What is an amphoteric substance?

    A substance that can act as either an acid or a base

  • 58

    Which of the following is an example of an amphiprotic substance?

    Bicarbonate (HCO₃⁻)

  • 59

    According to the Lewis definition, what characterizes a Lewis acid?

    It accepts an electron pair.

  • 60

    Which pair correctly matches the acid-base concept to its definition?

    Bronsted-Lowry acid: proton donor

  • 61

    Which definition of acids and bases is the most broadly applicable and does not require hydrogen ions?

    Lewis definition

  • 62

    What is formed when acids and bases neutralize each other?

    Water and a salt

  • 63

    In the reaction BF₃ + :NH₃ → BF₃NH₃, what is BF₃ acting as?

    Lewis acid

  • 64

    Which of the following is a characteristic of a strong acid according to the passage?

    It completely ionizes in water

  • 65

    Select all strong acids listed in the provided table.

    HI, HCl, H2SO4, HClO3, HNO3

  • 66

    According to the passage, what happens in the ionization of a weak acid?

    An equilibrium is established between the un-ionized species and its conjugate, Both reactants and products are present in the solution

  • 67

    Which of the following is a weak base according to the passage?

    (C2H5)NH, NH3, NH2NH2, NHOH, C5H5N

  • 68

    What does a large value of Ka or Kb indicate about an acid or base?

    It is a strong acid or base

  • 69

    Which of the following is NOT a characteristic of a weak base?

    It completely ionizes in water

  • 70

    Choose the strong bases from the table.

    LiOH, NaOH, Mg(OH)2, Ca(OH)2, Sr(OH)2

  • 71

    What is a polyprotic acid?

    An acid that can donate more than one acidic hydrogen

  • 72

    How does the ionization of polyprotic acids occur in water?

    Stepwise, with each hydrogen ion being released in a separate equilibrium step

  • 73

    How many steps does the ionization of carbonic acid occur in?

    Two

  • 74

    How many ionization steps does phosphoric acid have?

    Three

  • 75

    What process do water molecules undergo that leads to the formation of hydronium (H3O+) and hydroxide (OH-) ions?

    Auto-ionization

  • 76

    What is the value of the ion-product constant of water (Kw)?

    1.0 x 10^-14

  • 77

    What is the primary function of buffer systems in aqueous solutions?

    They resist changes in pH when small amounts of acid or base are added.

  • 78

    Which equation is commonly used to describe the behavior of buffer systems?

    The Henderson-Hasselbalch equation

  • 79

    In the buffer system involving hydrofluoric acid (HF) and its conjugate base (F⁻), what happens when a strong base is added?

    OH⁻ ions react with HF to form F⁻ and water, minimizing the increase in pH.

  • 80

    What does 'pH = -log[H₃O⁺]' represent?

    The mathematical definition of pH in terms of hydronium ion concentration

  • 81

    In the Henderson-Hasselbalch equation, what does [A⁻] represent?

    The concentration of the conjugate base

  • 82

    If a strong acid is added to a HF-F⁻ buffer, how does the buffer respond?

    F⁻ ions neutralize H⁺ ions, forming more HF and preventing a significant drop in pH.

  • 83

    What is the solution of known concentration used to react with the analyte called in titration?

    Titrant

  • 84

    In an acid-base titration, what does the indicator do?

    It changes color to signal the end point of the titration.

  • 85

    What term describes the point in titration when the amount of titrant added is stoichiometrically equivalent to the amount of analyte?

    Equivalence Point

  • 86

    What is the analyte in a titration?

    The substance whose concentration is being determined.

  • 87

    What does the 'End Point' in a titration refer to?

    The point at which the indicator changes color, signaling completion of the reaction.

  • 88

    Which component of titration is responsible for the color change that signals the end point?

    Indicator

  • 89

    During a titration, what needs to be known about the titrant?

    Its concentration.

  • 90

    What is titration primarily used for?

    To determine the concentration of an unknown solution.

  • 91

    Which of the following is NOT a key term in acid-base titration?

    Catalyst

  • 92

    If the indicator changes color before the equivalence point is reached, what is the main consequence for the titration?

    The calculated concentration of analyte will be inaccurate.

  • 93

    What type of chemical compounds are acid-base indicators?

    Compounds that change color when they undergo protonation or deprotonation

  • 94

    Why are acid-base indicators useful in titration?

    They change color at a specific pH range to approximate the equivalence point

  • 95

    What happens to an acid-base indicator in response to protonation or deprotonation?

    It changes color

  • 96

    What did the appearance of a pale pink color in the H2SO4 titration indicate?

    The endpoint of the titration

  • 97

    What is the formula used to calculate the molarity of HCl in the sample problem?

    M = amount of substance (mol) / volume (L)

  • 98

    How is phenolphthalein used to indicate the endpoint during titration?

    It turns pale pink at the endpoint

  • 99

    What is the balanced chemical equation for the reaction between Ba(OH)₂ and HCl?

    Ba(OH)₂ + 2HCl → BaCl₂ + 2H₂O

  • 100

    What color change does bromocresol green indicate at the endpoint?

    Yellow to blue

  • Strong Iodine Solution

    Strong Iodine Solution

    HERSHEY VALERIE BERNARDINO · 60問 · 4ヶ月前

    Strong Iodine Solution

    Strong Iodine Solution

    60問 • 4ヶ月前
    HERSHEY VALERIE BERNARDINO

    問題一覧

  • 1

    What is a solution?

    A homogeneous mixture composed of two or more substances.

  • 2

    In a salt water solution, what is the solvent?

    Water

  • 3

    Which component is usually present in a larger amount in a solution?

    Solvent

  • 4

    What term describes the substance that is dissolved in a solution?

    Solute

  • 5

    What interactions must be overcome for solution formation?

    Solute-solute and solvent-solvent interactions

  • 6

    What happens to NaCl when it dissolves in water?

    The ions separate and interact with water molecules.

  • 7

    What is solubility?

    The maximum quantity of solute that can dissolve in a specific amount of solvent at a particular temperature.

  • 8

    How is a supersaturated solution defined?

    A solution containing more solute than can normally dissolve at a given temperature.

  • 9

    If a solution contains less solute than its solubility at a certain temperature, how is it classified?

    Unsaturated

  • 10

    Which describes the interaction between the separated ions of salt and the surrounding water molecules?

    Solute-solvent interaction

  • 11

    What term describes a solution that contains less than the maximum amount of dissolved solute and can still dissolve more solute?

    Unsaturated

  • 12

    Which type of solution contains more dissolved solute than is normally possible at a given temperature and pressure, often leading to crystal formation upon cooling or seeding?

    Supersaturated

  • 13

    When the concentration of a solute in solution equals its solubility at a certain temperature and pressure, how is the solution described?

    Saturated

  • 14

    According to general trends, how does increasing temperature generally affect the solubility of solids in liquids?

    Increasing temperature increases solubility.

  • 15

    Which principle states that an increase in pressure increases the solubility of gases in liquids?

    Henry's Law

  • 16

    What phrase is used to describe the tendency of polar solutes dissolving best in polar solvents and nonpolar in nonpolar?

    Like dissolves like

  • 17

    Which of the following combinations would likely be highly soluble: nonpolar solute with nonpolar solvent, or polar solute with nonpolar solvent?

    Nonpolar solute with nonpolar solvent

  • 18

    What are some common examples of solid-in-liquid solutions?

    Salt in water, Sugar in water

  • 19

    Which factor does NOT directly affect the solubility of a solid in a liquid?

    Partial pressure

  • 20

    Alloys such as brass and bronze are examples of which type of solute-solvent combination?

    Solid in solid

  • 21

    The solubility of gases in liquids increases with which condition?

    Increasing partial pressure

  • 22

    When water vapor is present in air (composed of N₂, O₂, CO₂), which type of solution is formed?

    Gas in gas solution

  • 23

    Which of the following is a key factor that enhances the rate at which a solid dissolves in a liquid?

    Agitation (stirring)

  • 24

    Which of the following ions form compounds that are ALWAYS soluble in water?

    Nitrate (NO3-), Group 1 ions (Li+, Na+, K+, Rb+, Cs+), Ammonium (NH4+), Acetates

  • 25

    Which of the following salts is most likely to form a precipitate in water?

    Lead(II) sulfate (PbSO4)

  • 26

    What is a common exception for the solubility of sulfate salts?

    Ba2+, Ca2+, Sr2+, Pb2+, Hg2+, Ag+

  • 27

    Chromates are insoluble except with which ions?

    Group 1 ions, NH4+

  • 28

    Which group of compounds are always soluble, regardless of the cation or anion they are paired with?

    Nitrates, Acetates

  • 29

    Halides (Cl-, Br-, I-) are generally soluble. Which ions are exceptions, making the corresponding halides insoluble?

    Pb2+, Ag+, Hg2+

  • 30

    Which statement is TRUE about the solubility of hydroxide (OH-) compounds?

    Hydroxides are insoluble except with Group 1, NH4+, Ba2+, Ca2+, and Sr2+

  • 31

    If a salt contains a Group 1 cation, what can be said about its solubility in water?

    It is always soluble.

  • 32

    Which of the following compounds is insoluble in water?

    Calcium phosphate (Ca3(PO4)2)

  • 33

    Why are solubility rules important in chemistry?

    They help predict whether a substance will dissolve in water., They are essential for writing net ionic equations., They aid in preparing chemical solutions.

  • 34

    Which of the following best describes molarity?

    Moles of solute per liter of solution

  • 35

    Select all correct units commonly used to express concentration in chemistry.

    Molarity (mol/L), Percent concentration (%), Molality (mol/kg), Normality (eq/L), Parts per million (ppm)

  • 36

    Why is it important to use the correct and consistent unit of concentration in chemical experiments?

    To ensure accurate calculations and meaningful comparisons

  • 37

    Which expression correctly represents mass percent (% w/w)?

    (grams of solute / grams of solution) × 100

  • 38

    What is the definition of molality (m)?

    Moles of solute per kilogram of solvent

  • 39

    What does the process of dilution involve in terms of solute and solvent?

    Adding more solvent to decrease concentration while keeping the amount of solute unchanged.

  • 40

    What is the correct formula for dilution relating the concentrations and volumes before and after the process?

    C1V1 = C2V2

  • 41

    Which step comes FIRST when preparing a dilute solution from a concentrated stock solution?

    Measure a volume V1 from a stock solution with known concentration C1.

  • 42

    During the dilution process, what happens to the amount of solute present in the solution?

    It remains unchanged.

  • 43

    Why is dilution commonly performed in the laboratory?

    To prepare solutions from a more concentrated stock solution.

  • 44

    When 60 mL of 85% by volume H3PO4 is diluted to a total volume of 1.0 L, what is the final concentration by volume of the solution?

    5.10%

  • 45

    Given a solution with 245.0 g of H2SO4 dissolved in 1.000 L of solution (molar mass = 98.086 g/mol), what is the normality (N) of H2SO4 if it has two ionizable protons?

    5.0 N

  • 46

    Which of the following best defines 'percent by volume' in a solution?

    (Volume of solute/Volume of solution) × 100%

  • 47

    How many milliliters of an 85% by volume H3PO4 are required to prepare exactly 1.0 L of a 5.10% by volume solution?

    60 mL

  • 48

    A concentrated ammonia solution contains 28.0% w/w NH3 and has a density of 0.899 g/mL. What additional information is needed to calculate the molarity of the solution?

    The molar mass of NH3

  • 49

    What taste is characteristic of acids?

    sour

  • 50

    Which color does blue litmus paper turn in the presence of an acid?

    red

  • 51

    What gas is produced when acids corrode metals?

    hydrogen gas

  • 52

    According to the Arrhenius definition, what does a base produce in aqueous solution?

    OH⁻ ions

  • 53

    What ion is formed when H⁺ associates with water in solution?

    hydronium ion (H₃O⁺)

  • 54

    What is a key limitation of the Arrhenius definition of bases?

    It only includes substances that contain OH⁻ ions as bases.

  • 55

    In the Bronsted-Lowry definition, what is an acid?

    A proton donor

  • 56

    After a Bronsted-Lowry acid donates a proton, what does it become?

    Conjugate base

  • 57

    What is an amphoteric substance?

    A substance that can act as either an acid or a base

  • 58

    Which of the following is an example of an amphiprotic substance?

    Bicarbonate (HCO₃⁻)

  • 59

    According to the Lewis definition, what characterizes a Lewis acid?

    It accepts an electron pair.

  • 60

    Which pair correctly matches the acid-base concept to its definition?

    Bronsted-Lowry acid: proton donor

  • 61

    Which definition of acids and bases is the most broadly applicable and does not require hydrogen ions?

    Lewis definition

  • 62

    What is formed when acids and bases neutralize each other?

    Water and a salt

  • 63

    In the reaction BF₃ + :NH₃ → BF₃NH₃, what is BF₃ acting as?

    Lewis acid

  • 64

    Which of the following is a characteristic of a strong acid according to the passage?

    It completely ionizes in water

  • 65

    Select all strong acids listed in the provided table.

    HI, HCl, H2SO4, HClO3, HNO3

  • 66

    According to the passage, what happens in the ionization of a weak acid?

    An equilibrium is established between the un-ionized species and its conjugate, Both reactants and products are present in the solution

  • 67

    Which of the following is a weak base according to the passage?

    (C2H5)NH, NH3, NH2NH2, NHOH, C5H5N

  • 68

    What does a large value of Ka or Kb indicate about an acid or base?

    It is a strong acid or base

  • 69

    Which of the following is NOT a characteristic of a weak base?

    It completely ionizes in water

  • 70

    Choose the strong bases from the table.

    LiOH, NaOH, Mg(OH)2, Ca(OH)2, Sr(OH)2

  • 71

    What is a polyprotic acid?

    An acid that can donate more than one acidic hydrogen

  • 72

    How does the ionization of polyprotic acids occur in water?

    Stepwise, with each hydrogen ion being released in a separate equilibrium step

  • 73

    How many steps does the ionization of carbonic acid occur in?

    Two

  • 74

    How many ionization steps does phosphoric acid have?

    Three

  • 75

    What process do water molecules undergo that leads to the formation of hydronium (H3O+) and hydroxide (OH-) ions?

    Auto-ionization

  • 76

    What is the value of the ion-product constant of water (Kw)?

    1.0 x 10^-14

  • 77

    What is the primary function of buffer systems in aqueous solutions?

    They resist changes in pH when small amounts of acid or base are added.

  • 78

    Which equation is commonly used to describe the behavior of buffer systems?

    The Henderson-Hasselbalch equation

  • 79

    In the buffer system involving hydrofluoric acid (HF) and its conjugate base (F⁻), what happens when a strong base is added?

    OH⁻ ions react with HF to form F⁻ and water, minimizing the increase in pH.

  • 80

    What does 'pH = -log[H₃O⁺]' represent?

    The mathematical definition of pH in terms of hydronium ion concentration

  • 81

    In the Henderson-Hasselbalch equation, what does [A⁻] represent?

    The concentration of the conjugate base

  • 82

    If a strong acid is added to a HF-F⁻ buffer, how does the buffer respond?

    F⁻ ions neutralize H⁺ ions, forming more HF and preventing a significant drop in pH.

  • 83

    What is the solution of known concentration used to react with the analyte called in titration?

    Titrant

  • 84

    In an acid-base titration, what does the indicator do?

    It changes color to signal the end point of the titration.

  • 85

    What term describes the point in titration when the amount of titrant added is stoichiometrically equivalent to the amount of analyte?

    Equivalence Point

  • 86

    What is the analyte in a titration?

    The substance whose concentration is being determined.

  • 87

    What does the 'End Point' in a titration refer to?

    The point at which the indicator changes color, signaling completion of the reaction.

  • 88

    Which component of titration is responsible for the color change that signals the end point?

    Indicator

  • 89

    During a titration, what needs to be known about the titrant?

    Its concentration.

  • 90

    What is titration primarily used for?

    To determine the concentration of an unknown solution.

  • 91

    Which of the following is NOT a key term in acid-base titration?

    Catalyst

  • 92

    If the indicator changes color before the equivalence point is reached, what is the main consequence for the titration?

    The calculated concentration of analyte will be inaccurate.

  • 93

    What type of chemical compounds are acid-base indicators?

    Compounds that change color when they undergo protonation or deprotonation

  • 94

    Why are acid-base indicators useful in titration?

    They change color at a specific pH range to approximate the equivalence point

  • 95

    What happens to an acid-base indicator in response to protonation or deprotonation?

    It changes color

  • 96

    What did the appearance of a pale pink color in the H2SO4 titration indicate?

    The endpoint of the titration

  • 97

    What is the formula used to calculate the molarity of HCl in the sample problem?

    M = amount of substance (mol) / volume (L)

  • 98

    How is phenolphthalein used to indicate the endpoint during titration?

    It turns pale pink at the endpoint

  • 99

    What is the balanced chemical equation for the reaction between Ba(OH)₂ and HCl?

    Ba(OH)₂ + 2HCl → BaCl₂ + 2H₂O

  • 100

    What color change does bromocresol green indicate at the endpoint?

    Yellow to blue